# select # q.device_id, # u.university, # count(question_id) as question_cnt, # sum( # case # when result = 'right' then 1 # else 0 # end # ) as right_question_cnt # from question_practice_detail as q # left join user_profile as u on u.device_id =q.device_id and u.university ='复旦大学' # where month(da...